What if you had had a chance to kill Hitler?

Many people might have no doubts about being prepared to kill Hitler. But what if you were a prominent theologian? A noted pacifist? What then? That was exactly the dilemma that faced Dietrich Bonhoeffer, born 100 years ago, and one that led to his own death.

In the grey early morning of 9 April 1945, only weeks before the end of the war in Europe, a 39 year-old German Lutheran pastor was led naked to the gallows at Flossenbürg concentration camp in Bavaria.

As he walked to his death, he could hear the American artillery, the liberators who would arrive just 11 days later.

An SS prison doctor, who witnessed the scene, described the condemned man "kneeling on the floor praying fervently to his God".